DNSSEC and DANE for Exchange Online: turn the mail test green
SPF, DKIM and DMARC can be green while the mail test marks DNSSEC and DANE red. Sign your own zone first, then move MX off mail.protection.outlook.com.
Knowledge hub
Exchange Online
Reference you look up again: PowerShell, SharePoint, Teams, Purview and archiving. Not a blog, not a Microsoft clone — ways of working we use ourselves.
Overview of guides and release notes for Exchange Online. Or search the term on the whole site.
SPF, DKIM and DMARC for Microsoft 365: step by step to p=reject
Inventory your senders, publish one SPF record, switch on DKIM with 2048-bit keys, then DMARC from p=none with np=reject to p=reject. Tests each step with t=y (RFC 9989). With the records, PowerShell and checks.
SPF, DKIM and DMARC: every tag and switch explained
A complete reference to SPF mechanisms and qualifiers, DKIM key and signature tags, and every DMARC tag after RFC 9989, with a generator that builds the records for you and Microsoft 365 notes throughout.
